Defective Tire Or Set Up Error: Why Did Jorge Lorenzo Struggle At Le Mans?
Jorge Lorenzo's disappointing performance at the French Grand Prix at Le Mans has been the cause of some debate. The factory Yamaha man finished a lowly seventh, his worst finish (other than DNFs) since his rookie season in 2008, and finishing off the podium for the first time since Indianapolis in 2011. To say this was an uncharacteristic performance from Lorenzo is something of an understatement.
So what went wrong? Immediately after the race, Lorenzo made it clear that he believed the problem was with his rear tire. He had had no grip whatsoever, and been unable to get any drive from his rear tire. He told the press afterwards that the only logical explanation he could think of for his problems was a defective rear tire. Lorenzo had been fast in the morning warm up, though it was a little drier then, and the set up used was very similar to then. In 2012, Lorenzo had won at Le Mans by a huge margin, so he could not understand why he was struggling so badly in France.
Bridgestone naturally denied there had been a problem with Lorenzo's tire. After the race Bridgestone officials told the press that they had examined the tire together with Yamaha engineers and found nothing wrong with it. In their customary post-race press release, Bridgestone's Motorsport Tyre Development Manager Shinji Aoki reiterated this stance. "As is always the case in these situations, his engineer thoroughly examined Jorge’s race tyres which were found to be in good working condition," he is quoted in the press release as saying. "In addition, I examined the tyre myself and personally discussed the matter with the Yamaha engineers and we all agreed that Jorge’s lack of rear grip was not attributable to his tyre."
What do we know ourselves? Though nobody is saying anything other than official statements, there are still some clues we can piece together from the data available. The key fact is visible from the race footage, available to those with a MotoGP.com video pass on the official MotoGP website.
Jorge Lorenzo rides the sighting lap using the harder of the two wet compounds on his front tire. The hard front is clearly visible at the point 1'43 in the MotoGP.com footage (from here on in, all times will refer to this official footage), as it is the tire without the white banding on the sidewall. The white stripe on the sidewall is used by Bridgestone to signify that that particular tire is the softer of the two compounds available.
Lorenzo arrives at his grid slot 30 seconds later, and engages in a hurried discussion with his crew. He clearly asks for changes to be made, for at 2'32, Lorenzo's crew chief Ramon Forcada points at the front tire. A few seconds later, Lorenzo can be seen explaining a problem with the bike to a member of his crew (the team member has his back to the camera). Lorenzo's body language is clear, showing the front tucking, and the front wheel shaking. He appears to be indicating that he has a problem with grip at the front of the bike. A flurry of activity follows, as his crew begins to work on the bike.
On the basis of this advice, his crew decide to change the front tire for the softer option. This is borne out both by the tire selection sheet issued by Bridgestone after every race, and also by footage from the race. At the 22'14 mark in the footage, as the riders rounded the double right-hander at Raccordement at the end of the second lap, the footage shows a shot of Lorenzo's front wheel, in which the white stripe is clearly visible.
It seems a reasonable hypothesis to believe that the front tire swap was accompanied by a set up change, altering the balance of the bike to exploit the grip of the softer front tire. Whether or not they reverted completely to the settings used in the morning warm up when the track temperature was lower, and Lorenzo used the same tire combination, is unknown, Lorenzo only saying that the set up was "almost identical" to the set up used in the morning, with "slightly softer rear suspension".
But with neither Yamaha nor Bridgestone finding a problem with the tire, it seems safe to assume that it was this set up change which left Lorenzo without any grip. If a rider comes in from the sighting lap saying he has no grip on the front, then the natural reaction is to move the weight forward or lift the rear of the bike to put more weight on the front tire. Putting more weight on the front logically means you have less weight on the rear, and that results in less grip at the rear. That can be solved with suspension changes, but making those changes on the grid after the sighting lap gives you no chance to test that you got them right. In such difficult circumstances, with grip already lacking, a small miscalculation can have major consequences.
Logically examining the situation, it seems that the problem with Lorenzo's bike was not down to a defective rear tire. This conclusion would appear to be supported by Lorenzo himself, as the Spaniard deleted a couple of tweets on Sunday night, which he had posted earlier, and in which he suggested his rear tire was to blame. Was this an error by Lorenzo's crew? Arguably, but given the circumstances, such errors are easily made and impossible to rectify. Lorenzo made the best of a mediocre set up, coming home in seventh, but more importantly, coming home in one piece, and with a healthy 9 points scored.
The season is still long, though Lorenzo's deficit to Pedrosa of 17 points is larger than he would like. His poor result at Le Mans would appear to be just bad luck, one of those things that happens in racing. Ironically, for the second race in succession, Lorenzo has lost points due to what might be regarded as 'a racing incident'.